Apparatus for binding a winding head

ABSTRACT

An apparatus has a binding needle for binding a winding head having coils which extend beyond the frontal face of a magnetic core holding the winding sides of the coils. A pre-punch needle is provided. The pre-punch needle is radially movable with respect to the axis of the magnetic core. A motion producing member is operatively arranged to move the pre-punch needle into and out from interstices enclosed by the winding sides extending beyond the frontal face of the magnetic core, the winding head and the magnetic core. In operation the pre-punch needle widens the interstices before the binding needle is inserted into the interstices.

11 1 3,820,483 [4 June 28, 1974 United States Patent 1191 Her] et al.

[54] APPARATUS FOR BINDING A WINDING 3 024,746 3/1962 Hildmann 112/21 HEAD 3,440,979 4/1969 Frederick..................... 112/1212 [75] Inventors: Hans Her], Kongen; Klaus Hurlebaus plochingen; Fritz sauer Primary Eraminer-James R. Boler Esslingemsulzgries a of Germany Anorney, Agent, or Firm-Spencer & Kaye [73] Assignee: Licentia-Patent-Verwaltungs GmbH,

5 7] ABSTRACT An apparatus has a bindin ing h Frankfurt, Germany Apr. 21, 1972 g needle for binding a windead having coils whic ce of a magnetic core [22] Filed:

h extend beyond the frontal holding the windin unc'h needle is provided. The

21 App]. NO.3 246,247

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1,027,789 5/1912 112/85 4 Claims, 4 Drawing Figures APPARATUS FOR BINDING A WINDING HEAD BACKGROUND OF THE INVENTION This invention relates to an improvement in an apparatus for binding a winding head involving the widening of space between coils of a winding head. The present invention relates, more particularly, to an apparatus for widening the space between coils of a winding head whose coils extend beyond the associated frontal face of a magnetic core holding the winding sides of the coils. The winding head is to be tied into or wound about with a cord, a web or the like by means of a binding or tying apparatus having one or more binding needles.

Apparatuses and methods for binding or tying winding heads which have been inserted into the grooves of a magnetic core or the like, and which extend beyond its frontal faces are known. Such apparatuses and methods have been disclosed in the German Federal Republic Laid Open Pat. application No. 2,015,135 and in the U.S. Pat. No. 3,440,979. The principle according to which these prior art apparatuses function is generally as follows:

During binding or tying of a winding head, a binding needle provided at its front end with a hook portion is moved back and forth in a straight line between adjacent winding sides of the coils which form the winding head in the vicinity of the associated frontal face of the magnetic core, the binding needle cooperating with a further part, a cord or web supplier, which swings back and forth with a given rhythm above the winding head. While the cord or web supplier serves the purpose of radially tensioning the cord or web over the winding head, the binding needle serves the purpose of pulling the cord or web through the space enclosed by the winding sides, the winding head and the associated frontal face of the magnetic core, this being done also radially but below the winding head.

Particularly for low winding heads, where the coils extend only a small distance above the frontal face of the magnetic core, and in instances involving relatively small spaces between two adjacent winding sides, because of small spacing between the grooves in the core metal, it has been found that the insertion of the binding needle or needles presents substantial difficulties. Because of the desired high speed of operation of the binding needle, its movability transverse to the longitudinal axis, its cross section and its hook portion at the front, damage to the core metal as well as the individual wires of the winding sides often results.

SUMMARY OF THE INVENTION It is an object of the present invention to provide in an apparatus for binding a winding head an improvement whichsubstantially eliminates the possibility of damaging the binding needle during its movement.

It is another object of the present invention to provide in an apparatus for binding a winding head an improvement which substantially eliminates the possibility of damaging the wires of the coil sides from contact with the binding needle.

It is a further object of the present invention to provide in an apparatus for binding a winding head an improvement which substantially eliminates the possibility of damaging the face of the magnetic core from contact with the binding needle.

The foregoing objects, as well as others which will become apparent from the text below, are accomplished in accordance with the present invention in an apparatus having a binding needle for binding a winding head having coils which extend beyond the frontal face of a magnetic. core which holds the winding sides of the coils. A pre-punch needle is provided. The pre-punch needle is radially movable with respect to the axis of the magnetic core. A motion producing member is operatively arranged to move the pre-punch needle into and out from interstices enclosed by the winding sides extending beyond the frontal face of the magnetic core, the winding head and the magnetic core. The prepunch needle in operation widens the interstices before the winding needle is inserted into the interstices.

The present invention is characterized by the fact that the movement of the piercing needle is controllable in dependence on the operating rhythm of the binding needle, the control impulse for moving the piercing needle being derived in a particularly favorable manner from the drive shaft of the apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial perspective view of an apparatus for binding a winding head in accordance with an illustrative embodiment of the present invention.

FIG. 2 shows a wound magnetic core and the partial view of an apparatus working simultaneously on both sides of the magnetic core with two sets of needles.

FIG. 3 is a side view and FIG. 3a a plan view of the pre-punch needle.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, a magnetic core 1 formed of layers of individual metal sheets and serving either as the rotor or the stator core, has winding sides 2 of the individual coils accommodated in its grooves. The frontal connections of these coils protruding beyond the frontal face 3 of the magnetic core 1 form, in their entirety, the winding head generally designated by the numeral 4, interstices 5 being enclosed by the winding head 4, the frontal face 3 and the individual winding sides 2; The magnetic core 1 is positioned in the apparatus on a holding device which has an axis that coincides with the axis of the magnetic core 1 when the latter is in place. Such a holding device, which does not form part of the invention, may be similar to the stator guide sleeve of the aforementioned U.S. Pat. No. 3,440,979. A cord or web is to be pulled through the interstices 5 by a binding needle 6, which is part of the binding apparatus, so that the winding head 4 can be bound, the binding needle 6 being provided with a hooked portion 6 at its front end for this purpose.

As already mentioned, for lower winding heads and I v in instances involving relatively small spaces between adjacent winding sides, the binding needle 6 often damages the individual coil wires and the frontal face of the magnetic core 1 when the needle enters into the interstices 5, due to its particular cross section, its movability transverse to the longitudinal axis and its high operating speed. Damage tothe binding needle is also possible.

These drawbacks are substantially reduced or eliminated by a device, generally designated by the numeral 7, provided with a pre-punch needle 8 which is radially movable with respect to the axis of the abovementioned core holding device and thus to the axis of the magnetic core 1 and which is moved by a pneumatic cylinder 9 which itself is controlled according to the operating rhythm of the binding needle 6. The control of the cylinder 9 is effected to produce perfect synchro- In operation, the binding apparatus rotates magnetic core 1 in a clockwise direction over the drive shaft in a certain-operating rhythm about its own axis, for example, by two, three or four groove divisions at a time, depending on the selected design of the winding head winding. The binding needle 6 accordingly is inserted only into each second, third or fourth interstice as is the pre-punch' needle 8 which precedes the binding needle 6. As shown in FIG. 1, the pre-punch needle 8 is so designed that it widens each of the interstices 5 as it sequentially enters them. This is so because the prepunch needle 8 is widened toward its rear end as shown in FIGS. 3 and 3a. Widening of the coil interstices is effected to such an extent that the binding needle 6 can be inserted without any interference or damage.

Alternatively, the interstices 5 may advantageously be widened by a pre-punch needle with a wedging means which is in the form of a pliers-like member having a front end which can be spread out while it is inserted in each of the interstices to be widened.

For widening the interstices 5 of the winding heads 4 on both frontal faces 3 of the magnetic core 1 simultaneously before binding, the apparatus comprising as shown in FIG. 2 a second binding needle 6 and a second device 7, equally provided with a pre-punch needle 8 which is radially movable with respect to the axis of the magnetic core 1 and which is moved by a pneumatic cylinder 9 which itself is controlled according to the operating rhythm of the binding needle. Both devices 7 and both binding needles 6 are simultaneously moved from the drive shaft of the binding apparatus, indicated by the interrupted lines.

The advantages attained with the present invention are in particular that the widening of the interstices between the coil sides can take place on easily modified available binding apparatuses so that this additional operating step does not result in any loss in time. Furthermore, the modification of known binding apparatuses is relatively simple and assures a. logical operating rhythm control for the pre-punch needle with the already present binding needle and a precentering of the magnetic core or the interstices, respectively, by the pre-punch needle. The primary advantage, however, is that the prior widening assures substantially fault-free winding of the winding head so that the reject losses due to damage can be kept very low.

It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations,- and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims.

We claim:

1. In apparatus having a binding needle for binding a winding head having coils which extend beyond the frontal face of a magnetic core holding the winding sides of the coils, the magnetic core being positioned in said apparatus on holding means defining an axis that coincides with the axis of the magnetic core, the improvement comprising, in combination:

a pre-punch needle which is radially movable with respect to the axis of said holding means; said prepunch needle having wedging means; and means coupled to said pre-punch needle for moving it radially with respect to the axis of said holding means into and out from interstices enclosed by the winding sides extending beyond the frontal face of the magnetic core, the winding head and the magnetic core,

whereby said pre-punch needle widens the interstices with said wedging means before said binding needle is inserted into the interstices.

2. An arrangement as defined in claim 1 wherein said pre-punch needle widens toward its rear end.

3. An arrangement as defined in claim 1 further comprising a second pre-punch needle which is radially movable with respect to the axis of said holding means and which is disposed near a side of the magnetic core opposite to the side of the magnetic core near which the first said pre-punch needle is disposed, and means for moving said second pre-punch needle radially with respect to the axis of said holding means into and out of interstices enclosed by the winding sides. extending beyond the frontal face of the magnetic core, a second winding head and the magnetic core, whereby the interstices associated with two oppositely disposed winding heads, are widened simultaneously before binding.

4. An arrangement as defined in claim 1, said means coupled to said pre-pun'ch needle being controlled in synchronism with the operating rhythm of said binding needle. 

1. In apparatus having a binding needle for binding a winding head having coils which extend beyond the frontal face of a magnetic core holding the winding sides of the coils, the magnetic core being positioned in said apparatus on holding means defining an axis that coincides with the axis of the magnetic core, the improvement comprising, in combination: a pre-punch needle which is radially movable with respect to the axis of said holding means; said pre-punch needle having wedging means; and means coupled to said pre-punch needle for moving it radially with respect to the axis of said holding means into and out from interstices enclosed by the winding sides extending beyond the frontal face of the magnetic core, the winding head and the magnetic core, whereby said pre-punch needle widens the interstices with said wedging means before said binding needle is inserted into the intersticeS.
 2. An arrangement as defined in claim 1 wherein said pre-punch needle widens toward its rear end.
 3. An arrangement as defined in claim 1 further comprising a second pre-punch needle which is radially movable with respect to the axis of said holding means and which is disposed near a side of the magnetic core opposite to the side of the magnetic core near which the first said pre-punch needle is disposed, and means for moving said second pre-punch needle radially with respect to the axis of said holding means into and out of interstices enclosed by the winding sides extending beyond the frontal face of the magnetic core, a second winding head and the magnetic core, whereby the interstices associated with two oppositely disposed winding heads are widened simultaneously before binding.
 4. An arrangement as defined in claim 1, said means coupled to said pre-punch needle being controlled in synchronism with the operating rhythm of said binding needle. 